Camshaft phasers are utilized within IC engines to adjust timing of engine valve events to optimize performance, efficiency and emissions. Many different camshaft configurations are possible within an IC engine. Some configurations include an intake camshaft that actuates intake valves, and an exhaust camshaft that actuates exhaust valves; such camshaft configurations can often simplify efforts to independently phase the intake valve events separately from the exhaust valve events. Other camshaft configurations can utilize a single camshaft to actuate both intake and exhaust valves; however, a single camshaft configured with both intake and exhaust lobes makes it difficult to provide independent phasing of the intake and exhaust valves. For this reason, a concentric camshaft arrangement can be implemented that utilizes two camshafts, an inner camshaft and an outer camshaft, each arranged with one of either exhaust lobes or intake lobes. A solution is required for a camshaft phaser arrangement that provides independent phasing of the intake and exhaust valves for an IC engine configured with a concentric camshaft assembly.